Grinding-machine.



F. S. BURT 6: C. L. ROWE.

GRINDING MACHINE.

APPLICATION FILED SEPT- I7. 1915.

Patented May 23,1916.

FRANK S BURT AND CLYDE L. ROWE, OF CHICAGO, ILLINOIS, ASSIGNORS TO QUICK- EDGE SHARPENEB 00., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

GRINDING-MACHIN E.

To all whom it may concern:

Be it known that we, FRANK S. BURT and CLYDE L. Rowe, both citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Grinding-l/lachines, of which the following is a specification.

This invention relates to a grinding ma chine for sharpening blades and performing similar work, and is concerned with a novel construction and arrangement of parts for accomplishing the grinding operations.

Our invention has for its objects the construction of a grinding machine which is simple, inexpensive, and durable, and which is otherwise fitted to fulfil the usual requirements of devices of this character; a grinding machine wherein the grinding surfaces are so arranged with respect to the work as to insure effective action upon the work; a grinding machine having guides or holders for the work, and capable of adjustment with reference to the particular size or shape of the work, and capable also of yielding to meet the requirements of the work.

The invention consists further in numerous other features of construction and combinations of parts as will more fully hereinafter appear.

In the drawing: Figure 1 is a plan view of agrinding machine constructed in accordance with our invention; Fig. 2 is a side elevation of the machine looking toward the side upon which the manual operating means is situated; Fig. 3 is a side elevation of the machine, looking upon the reverse side to that shown in Fig. 2; and Fig. 4 is a diagrammatic perspective View showing the relation of the grinding surfaces to the work.

The present grinding machine comprises a hollow frame 5 from the lower end of which two shoulders 6 and 7 project laterally, a thumb screw 8 being threaded through the latter of these shoulders. This construction enables the framework to be secured adjacent the edge of a table, shelf, or other fixed support, for the purpose of maintaining the machine stationary while the grinding operation takes place. Within the frame of the machine is journaled a toothed driving wheel 9, the shaft 10 of which extends through the frame. A crank 11 having a handle 11 is locked to the shaft 10,

Specification of Letters Patent.

Application filed September 17, 1915.

Patented May 23, 1916.

Serial No. 51,254.

and it is by this means that the driving wheel may be manually operated. J ournaled within the hollow frame 5 are three other shafts 12, 13, and ll, each carrying a pinion, designated respectively as 15, 16, and 17. The pinions l5 and 16 are each in mesh with the driving gear 9. The pinion 17 however is driven from the pinion 16 with which it is meshed, this arrangement enabling the pinions 15 and 17 to revolve in opposite directions when the driving wheel 9 is rotated.

The shafts 12 and 14 each extend through to the outside of the frame 5, being extended upon the side opposite the operating handle. Grinding wheels 18 and 19 respectively are secured to the ends of these shafts 12 and 14, being revolved in opposite directions when the driving wheel is operated. These grinding wheels are so arranged, moreover, as to overlap each other, this clearly appearing from the several figures in the drawing. The form of these grinding wheels is such that a flat peripheral portion 20 is provided, and also a beveled peripheral portion 21. In the arrangement shown, the beveled portions face inwardly and are in proximity to each other. lifeans for holding the work in grinding position are also provided, consisting of two arms 22 and 23, each bent generally in the form of a semi-circle as appears best in Fig. 3. These arms are secured to the frame in any suitable manner, such for instance, as by screws 24, best shown in Fig. 3. The form of these arms is such that they each lie outside of the shafts 12 and 14, and close to the overlapping surfaces of the grinding wheels secured to those shafts. We prefer that the fastening means, such as the screws 24, should. be slightly less in diameter than the size of the openings in the arms 22 and 23 through which the screws pass, so that these arms may each be adjusted in any one of several positions within close limits, prior to tightening of the screws. The object and purpose of this construction, which is shown by dotted lines in Fig. 3, will appear elsewhere in this specification.

The extremities 25 and 26, respectively, of the arms 22 and 23 are overlapped and inclined at substantially the same angle as the beveled edges of the grinding wheels. The form and material in which the arms 22 and 23 are made may be selected to impart to them a certain amount of tension or resilition.

in position so that a proper grinding action is insured. here, for instance, a knife blade is to be sharpened, it is necessary that the blade be moved back and forth across the grinding surfaces of the wheels. In the construction we have shown, this back and forth movement may be maintained in a substantially straight line between the guiding ends of the arms, and over the grinding surfaces of the wheels. In cases where the work requires that the guiding ends of the arms should yield considerably, the screws 24 may be loosened, and the arms 22 and 23 be adjusted to a new position.

It will be noted, moreover, that the grinding wheels which we have shown not only overlap each other, but are provided with beveled edges which face each other. The grinding action of a beveled edge upon the work is not comparable to that of a straight or flat edge. In the case of a beveled grinding surface, there is developed a sidewise or lateral frictional engagement which assists materially in the grinding action.

It will be noted that each of the grinding wheels is provided with a flat peripheral surface, as well as a beveled surface, and

that a member 27 is shown extending adja-' cent the flat surface of the wheel 19. This is for the purpose of steadying or holding work in position, which can best be acted upon by a flat grinding surface rather than by a surface which is beveled.

From the description of our invention, it will be apparent that the present grinding machine is exceedingly simple of construction, and is well adapted to meet the requirements of devices of this kind. Obviously certain changes and modifications may be made from the precise construction which we have shown and described without in any way departing from the scope of our inven- VVe claim:

1. In a grinding machine, the combination with a frame, of companion grinding wheels each formed with a beveled circumferential edge, said wheels being rotatably mounted upon the frame in overlapping adjacent positions with their beveled edges facing toward each other, means secured to the frame for holding the work in operative position upon the wheels comprising a pair of arms Copies of this patent may be obtained for each provided with a guiding portion for the work disposed at an angle substantially the same as the beveled edges of the wheels, whereby the work is held between the wheels in alinement with the beveled edges thereof, and means for revolvingthe grinding wheels simultaneously in opposite directions, substantially as described.

2. In a grinding machine, the combination .70

with a frame, of companion grinding wheels each formed with a beveled circumferential edge, said wheels being rotatably mounted upon the frame in overlapping adjacent positions with their beveled edges facing toward each other, means secured adjustably to the frame for holding the work in operative position upon the wheels comprising a pair of tension arms each provided with a guiding portion for the work disposed at an angle substantiallythe same as the beveled edges ofthe wheels, whereby the work is held between the wheels in alinement with the beveled edges thereof, and means for revolving the grinding wheels simultaneously in opposite directions, substantially as described.

3. In a grinding machine, a combination with a frame, of companion grinding wheels each formed with a beveled circumferential edge, said wheels being rotatably mounted upon the frame in overlapping adjacent positions with their beveled edges facing toward each other, means for holding the work in operative position comprising a pair of arms secured to the frame, guiding portions on said arms disposed at an angle substan tially the same as the beveled edges of the wheels, and arranged to retain the work therebetween in alinement with the beveled V edges of the wheels, and means for revolv ing the grinding wheels simultaneously in FRANK S. BURT.

CLYDE L. ROWE.

WVitne'sses: i I

MYRoN B. HART, HERTHA M. NIELSEN.

five cents each, by addressing the "Commissioner of Patents,

Washington, D. G. 

